Sure -
F = mr (omega)^2 = mg
m's cancel out - we get g = r (omega)^2 where g is acceleration due to gravity, r is radius to earth's center of mass, and omega is rotational velocity of the object around the earth.
You can also go one step further and solve for v = r (omega) where v is the horizontal velocity.
Then g = v^2 / r
Checking units, we get ft / sec^2 = (ft^2/sec^2)/ft
So v = square root (rg)
Makes sense to me - perhaps a little oversimplified, but close enough for a reasonable estimate.
ADDED -
You may be looking for the velocity required to leave earth orbit. At launch, escape velocity is about 7 miles / second.
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